Radial compressors, also called centrifugal compressors, of different types are used in various areas. One example is the exhaust gas recirculation (EGR) compressor, which can be used to reduce nitrogen oxide (NOx) emissions caused by an engine like a petrol engine or a diesel engine. The EGR compressor is used particularly in different types of vehicles, for instance, in ships.
A common radial compressor comprises a motor with different bearings. Further, a common radial compressor comprises at least one sealing, particularly at the shaft of the compressor's motor. The common radial compressor has multiple external pipes (external pipework) to supply the bearings with oil and the sealing with sealing air.
One objective of the invention is to provide a radial compressor with an enhanced design, especially with a robust design.
This objective is accomplished by means of a radial compressor according to claim 1.
I.E., this objective is accomplished by means of a radial compressor of the type mentioned in the introduction, wherein, according to the invention, the distribution system is an integral part of the housing. Further, the housing comprises several housing parts, which are connected to each other and which are arranged adjacent to each other in longitudinal direction of the shaft. Moreover, the distribution system extends through at least two of the housing parts.
A housing for the motor in the meaning of this invention may be a housing, which is embodied to cover the motor. Further, a distribution system for a service fluid for the motor in the meaning of this invention may be a distribution system, which is embodied to conduct the service fluid to the motor.
An integral part of the housing in the meaning of this invention may be a direct part of the housing. Further, since the distribution system is an integral part of the housing, the distribution system may be incorporated into and/or worked into the housing. Particularly, the distribution system and the housing may comprise the same material. Thus, the distribution system and the housing may be manufactured from the same material. For instance, the distribution system and the housing may be formed in one piece, particularly at least partially.
The distribution system and/or at least one of its elements—particularly the main feed, the manifold and/or the feed branches—may be a cavity and/or a hollow space. Further, the distribution system and/or at least one of its elements may be formed by the walls of the housing. Further the distribution system and/or at least one of its elements may be drilled in the housing. Moreover, the walls of the distribution system can be uncoated, partially coated or coated.
Expediently, the several housing parts are separate housing parts. Each of the several housing parts may house a specific part of the radial compressor. For instance, a housing part can be a rear plate, a main housing and/or a bearing housing. Further, the distribution system may comprise several parts.
Each part of the distribution system or each group/subgroup of parts of the distribution system may be an integral part of the respective housing part. Preferably, each part of the distribution system or group/subgroup of parts of the distribution system and the respective housing part are formed in one piece. The housing parts can be connected by flanges with each other.
The invention is based on the observation that a radial compressor is often directly connected to an engine. Particularly, the radial compressor can be directly flange mounted to an engine. Thus, vibrations from the engine are transferred to the compressor. External pipes at the radial compressor are fragile and may break easily due to the vibrations during usage. Thus, the suggestion is to integrate former external supply elements like external pipes into the housing for the motor (following called housing). An integrated distribution system within the housing will be much more robust than external supply elements.
A further advantage is, that a radial compressor with an integrated distribution system will be much more compact than a radial compressor with external supply elements. Thus, the radial compressor with an integrated distribution system will be easy to handle, especially during the shipping process. Hence, the radial compressor will be robust during shipping as well as during usage.
By the fact that the several housing parts are arranged adjacent to each other in longitudinal direction of the shaft, the housing is more robust against vibrations than a housing, which e.g. is split along a centerline axis of the housing. Moreover, the risk of oil leakages is decreased by arranging the housing parts adjacent to each other in longitudinal direction of the shaft. Further, by the fact that the several housing parts are arranged adjacent to each other in longitudinal direction of the shaft, radial compressor may be easy to mount and, if necessary, easy to dismount. Moreover, the housing parts can be manufactured easily.
Since the distribution system extends through at least two of the housing parts, the housing may be easy to construct and easy to manufacture.
The distribution system may be a distribution system for an integrated supply of service fluid. Thus, the distribution system may conduct the service fluid directly within the housing. Particularly, the main feed may be a main feed for supplying the distribution system with the service fluid. For instance, the service fluid may enter the housing, particularly the distribution system, through the main feed. Further, the main feed may conduct the service fluid towards the manifold. Moreover, the manifold may conduct the service fluid into the feed branches.
Expediently, the manifold comprises a branching point/branching region for the feed branches and, if necessary, the main feed. In a preferred embodiment of the invention, the manifold may be a branching linker for the feed branches and, if necessary, the main feed. Hence, the manifold may be compact.
Further, it is advantageous that each feed branch is built by a conduit.
The at least two feed branches may be exactly two feed branches or more than two, e.g. three, four or even more, feed branches. The manifold may be configured according to the number of feed branches joining in the manifold.
Advantageously, at least one of the feed branches of the distribution system extends through at least two of the housing parts.
At least one feed branch may comprise several segments. Particularly, the at least one feed branch, which expediently extends through at least two of the housing parts, may comprise several segments. A first of the several segments may be arranged within one of the several housing parts. Further, a second of the several segments may be arranged within another of the several housing parts. Preferably, the first segment opens out into the second segment, and expediently vice versa.
It is preferred, if the radial compressor is a turbo compressor. Advantageously, the radial compressor is an exhaust gas recirculation compressor. An exhaust gas recirculation compressor normally is directly (flange) mounted to an engine. Thus, vibrations from the engine are transferred to the radial compressor. Especially in this case, it is expedient to integrate the distribution system into the housing so that the housing may get more robust and/or more compact.
In an advantageous embodiment of the invention, the service fluid is oil. Optionally, the service fluid may be another lubricating fluid. The service fluid may lubricate the motor of the radial compressor, particularly the shaft of the motor.
Preferentially, the radial compressor comprises at least one bearing. The at least one bearing may support and/or mount the shaft of the motor. Expediently, the main feed is inflow connection with the at least one bearing of the radial compressor, particularly to lubricate the bearing. The bearing may be oil lubricated. For instance, the bearing can be a journal bearing, a thrust bearing or a counter bearing. The distribution system, particularly the feed branches, may conduct the service fluid, i.e. the oil, to the at least one bearing. Hence, the distribution system conducts the service fluid to the motor, particularly to the bearings of the motor.
For instance, the radial compressor may comprise two or more bearings, which may be locally separated from each other. Each bearing can be a journal bearing, a thrust bearing or a counter bearing. Further, each feed branch may conduct service fluid to the respective bearing.
Advantageously, a service fluid supply is connectable to the distribution system, particularly to the main feed of the distribution system. The service fluid supply may supply the radial compressor, particularly rotating elements of the radial compressor, via the distribution system with service fluid.
Further, the distribution system, particularly the main feed, can comprise a connecting element, particularly for attaching the service fluid supply. For instance, the distribution system, particularly the main feed, can comprise a flange connection and/or a fitting, particularly to be able to connect the service fluid supply to the distribution system. Moreover, the flange connection and/or the fitting may be accessible directly from outside. Preferentially, the flange connection and/or the fitting are/is an integral part of the housing. Further it is possible, that the fitting may be a separate part, which is connected with the housing. By means of the flange connection and/or fitting, the service fluid supply is connectable to the distribution system, particularly to the main feed of the distribution system. Particularly, the flange connection and/or the fitting may be connectable with the service fluid supply.
In a preferred embodiment of the invention, the housing for the motor comprises a protrusion. Preferentially, the protrusion is an integral part of the housing. Further, the protrusion may comprise at least a part of the distribution system. The protrusion can be formed like a ligament, a slat, a bar and/or a fin or miscellaneous. Further, the protrusion can be formed corresponding to the form of the distribution system and/or parts of the distribution system.
Further, it is advantageous, if the housing for the motor comprises a base body, particularly a rotationally symmetric base body. Moreover, the protrusion may be arranged at the base body.
A protrusion in the meaning of this invention may include additional material at the housing, which may build up the distribution system at least partially.
The distribution system may have a complex form and/or may be a complex conduct system. The protrusion may comprise several protrusion parts, particularly to reproduce the complexity of the distribution system. Further, the distribution system may extend more than one housing part. Thus, also the protrusion may extend more than one housing part. Following, the protrusion may comprise several protrusion parts, wherein each protrusion part or each group/subgroup of protrusion parts may be an integral part of the respective housing part. Preferably, each protrusion part or each group/subgroup of protrusion parts and the respective housing part are formed in one piece.
The feed branch may comprise an arbitrary cross sectional form, particularly a round, ellipse-shaped or rectangular cross sectional form. Further, the feed branch comprises a diameter and/or a width. The cross sectional form and/or the diameter/width of the feed branch may change over a length of the feed branch. Preferentially, a diameter/width of the feed branch is an averaged width of a feed branch. A length of the feed branch may be at least 15 times, particularly at least 20 times, preferentially at least 25 times, even more preferred at least 30 times, of a diameter of the feed branch.
The housing of the motor may be formed arbitrarily. For instance, the housing of the motor can be formed rotationally symmetrically. The housing and/or the housing parts can have a length, a width and/or a diameter. With the distribution system being an integral part of the housing and/or of several housing parts, the length of the feed branch may be at least 60%, particularly at least 70%, preferentially at least 80%, of a diameter/a width of a housing and/or of the respective housing parts.
Further, the arrangement/design implies also a method for conducting a service fluid within the radial compressor described above.
Further, the radial compressor may comprise a gas supply system for a gas sealing of the motor. To provide a radial compressor with an enhanced design, especially with a robust design, the gas supply system may comprise a gas conduit and a fitting, wherein the gas conduit may be an integral part of the housing, through which gas conduit a gas can be conducted towards the gas sealing, and the fitting is arranged in the area of a hole top of the gas conduit.
Particularly the integrated gas conduit may allow a robust and/or compact radial compressor.
Preferably, the gas conduit is a cavity and/or a hollow space. The gas conduit may be formed by the walls of the housing.
The fitting may be screwed into the conduit, particularly into the hole top of the conduit. Thus, the fitting can be detachable and/or exchangeable. Further, the fitting may be glued into/pasted into the conduit, particularly into the hole top of the conduit. Moreover, the fitting may be pressed tightly into the conduit, particularly into the hole top of the conduit.
Expediently, the fitting is accessible directly from outside, particularly for supplying the gas conduit with the gas. The gas may be sealing air. Further, the gas can be a compressed gas.
Preferably, the gas conduit connects the fitting with the gas sealing of the radial compressor directly, particularly to seal the shaft of the motor. Further, the gas supply system may conduct the gas to the gas sealing. The gas sealing may be arranged on the shaft of the motor. Thus, the gas conduit may conduct the gas directly to the gas sealing.
Further, the gas conduit may be straight, particularly to have a short connection from the fitting to the gas sealing. The fitting may be arranged at the housing in a way, that the fitting is accessible. Moreover, the fitting may be arranged at the housing in a way, that the gas conduit is short, particularly as short as possible.
It is advantageous, if a gas supply is connectable to the fitting. The gas supply may supply the gas supply system with gas. Therefore, the fitting of the gas supply system may be a connecting element for attaching the sealing air supply.
The gas conduit may be uncoated, partially coated or coated. Further, the gas conduit may comprise an arbitrary cross sectional form, particularly a round, ellipse-shaped or rectangular cross sectional form. Moreover, the gas conduit comprises a diameter and/or a width. The cross sectional form and/or the diameter/width of the gas conduit can stay constantly and/or may change over a length of the gas conduit. Preferentially, a diameter/width of the gas conduit is an averaged width of a gas conduit. A length of the gas conduit may be at least 15 times, particularly at least 20 times, preferentially at least 25 times, even more preferred at least 30 times, of a diameter of the gas conduit.
The housing may comprise several housing parts. For instance, the gas supply system can be a part of one of the housing parts. Further, the housing of the motor may be formed arbitrarily. For instance, the housing of the motor can be formed rotationally symmetrically. The housing and/or the housing parts can have a length, a width and/or a radius. With the distribution system being an integral part of the housing and/or of one housing part, the length of the gas conduit may be at least 60%, particularly at least 70%, preferentially at least 80%, of a radius of the housing and/or of the respective housing part.
Preferentially, the gas sealing is working with compressed gas. Further, the gas sealing can be a labyrinth sealing. Alternatively, another gas sealing type is possible as well.
Further, the arrangement/design implies also a method for conducting a gas within the radial compressor described above.
Moreover, the invention relates to an exhaust gas recirculation system comprising the radial compressor according to the invention and/or an embodiment thereof. Further, the exhaust gas recirculation system comprises a combustion chamber.
According to the invention, an output of the combustion chamber is connected with an input of the radial compressor. The exhaust gas recirculation system may be embodied to conduct at least part of the exhaust of the combustion chamber to the radial compressor. Preferably, at least the part of the exhaust of the combustion chamber is compressed by means of the radial compressor.
Further, according to the invention, an output of the radial compressor is connected to an input of the combustion chamber. The exhaust gas recirculation system may be embodied to conduct at least the compressed exhaust to the combustion chamber.
A temperature of the combustion chamber during combustion may be reduced by means of the recirculation of at least part of the exhaust. Advantageously, less NOx is produced due to the lower combustion temperature. In this way, the exhaust gas recirculation system may reduce NOx emissions.
Even if terms are used in the singular or in a specific numeral form, the scope of the invention should not be restricted to the singular or the specific numeral form.
The previously given description of advantageous embodiments of the invention contains numerous features which are partially combined with one another in the dependent claims. Expediently, these features can also be considered individually and be combined with one another into further suitable combinations. More particularly, these features may be combined with the can and the method according to the respective independent claim individually as well as in any suitable combination. Furthermore, features of the method, formulated as apparatus features, may be considered as features of the can and, accordingly, features of the can, formulated as process features, may be considered as features of the method.
The above-described characteristics, features and advantages of the invention and the manner in which they are achieved can be understood more clearly in connection with the following description of exemplary embodiment which will be explained with reference to the drawings. The exemplary embodiment is intended to illustrate the invention, but is not supposed to restrict the scope of the invention to combinations of features given therein, neither with regard to functional features. Furthermore, suitable features of each of the exemplary embodiments can also be explicitly considered in isolation and/or be combined with any of the appended claims.